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Matter-antimatter asymmetry generated by LQG

  1. Feb 7, 2004 #1


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    Meteor just posted a link in the "surrogate sticky" LQG referemce library to an article by Parampreet Singh.

    A propos of Singh, he has had several interesting articles recently relating LQG and the big bang---using Loop Gravity to predict inflation, to eliminate singularity (replace crunch by bounce) as well as this one. Here he and his co-author use LQG to explore Matter-Antimatter Asymmetry (one of the outstanding puzzles in the Standard Model)

    Gaetano Lambiase and Parampreet Singh
    "Matter-antimatter asymmetry generated by Loop Quantum Gravity"
    http://arxiv.org/gr-qc/0304051 [Broken]

    The article was published last year in Physics Letters
    Phys.Lett. B565 (2003) 27-32

    Here's a quote from the conclusions paragraph. I bolded a sentence for emphasis:

    ---quote from Lambiase/Singh---
    An intriguing prediction of modern approaches to quantum gravity is a slight departure from Lorentz’s invariance, which manifests in a deformation of the dispersion relations of photons and fermions. Such results have been indeed suggested in Loop Quantum Gravity [24,5,6], String Theory [11,12] and Non-Commutative Geometry [10].

    The former is endowed with a scale length characterizing the scale on which new effects are non trivial, thus to wonder if there exist different scenarios where these effects become testable (see [17,36]) is certainly of current interest.

    In this letter we have shown that such modifications induced by Loop Quantum Gravity might help to put some light on unsolved problems like matter-antimatter asymmetry in Standard Model. Application of weave states for Majorana fermions naturally leads to difference in energies for different chiralities which may be interpreted as
    difference in particle and antiparticle energies for the case of massless neutrinos. This leads to asymmetry between matter and antimatter species and yields the observed value at around reheating temperatures.

    Our proposal introduces a way for generation of matter-antimatter asymmetry via Loop Quantum Gravity, whose complete analysis would require relaxing the massless limit and secondly taking into account various standard model interactions in unison with Loop Quantum Gravity. Then we shall be able to know how the above mechanism to generate matter-antimatter asymmetry contributes relative to other processes. This opens up a new arena to make phenomenological studies in Loop Quantum Gravity in future.

    It is a remarkable phenomena that quantum structure of spacetime itself may generatematter-antimatter asymmetry in the Universe. In fact, this might be a generic feature of theories of Quantum Gravity. It reflects that Quantum Gravity may lead to effects occurring at lower energy scales, specially in the desert between electroweak and Planck scale, which may provide natural answers to some unsolved problems.
    -------end quote----------
    Last edited by a moderator: May 1, 2017
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  3. Feb 7, 2004 #2


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    I went and looked up other papers by Lambiase and he has published quite a lot including in String. But here (together with the one with Singh) are a couple of other recent ones he published last year:

    1. gr-qc/0304051 [abs, ps, pdf, other] :
    Title: Matter-Antimatter Asymmetry Generated by Loop Quantum Gravity
    Authors: Gaetano Lambiase, Parampreet Singh
    Comments: To appear in Phys. Lett. B.
    Journal-ref: Phys.Lett. B565 (2003) 27-32

    2. gr-qc/0302053 [abs, ps, pdf, other] :
    Title: Spin Flavor Conversion of Neutrinos in Loop Quantum Gravity
    Authors: G. Lambiase
    Comments: 7 pages, no figure
    Journal-ref: Class.Quant.Grav. 20 (2003) 4213-4220

    3. gr-qc/0301058 [abs, ps, pdf, other] :
    Title: Cerenkov's Effect and Neutrino Oscillations in Loop Quantum Gravity
    Authors: G. Lambiase
    Comments: 6 pages, no figures, in print on MPLA
    Journal-ref: Mod.Phys.Lett. A18 (2003) 23-30

    Also checked for other papers by Singh
    and found a recent one co-authored by Roy Maartens and Shinji Tsujikawa. Its in the "Loop Quantum Cosmology" batch of the surrogate sticky reference library

    Tsujikawa, Singh, Maartens
    "Loop quantum gravity effects on inflation and the CMB"

    Tsujikawa and Maartens have written String papers in the past. This seems to be their first venture into LQG cosmology.
    Last edited: Feb 7, 2004
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